| /* |
| * |
| * Copyright (C) 2007 Google, Inc. |
| * Copyright (c) 2009-2012, The Linux Foundation. All rights reserved. |
| * |
| * This software is licensed under the terms of the GNU General Public |
| * License version 2, as published by the Free Software Foundation, and |
| * may be copied, distributed, and modified under those terms. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| */ |
| |
| #include <linux/clocksource.h> |
| #include <linux/clockchips.h> |
| #include <linux/cpu.h> |
| #include <linux/init.h> |
| #include <linux/interrupt.h> |
| #include <linux/irq.h> |
| #include <linux/io.h> |
| #include <linux/of.h> |
| #include <linux/of_address.h> |
| #include <linux/of_irq.h> |
| #include <linux/sched_clock.h> |
| |
| #include <asm/mach/time.h> |
| |
| #include "common.h" |
| |
| #define TIMER_MATCH_VAL 0x0000 |
| #define TIMER_COUNT_VAL 0x0004 |
| #define TIMER_ENABLE 0x0008 |
| #define TIMER_ENABLE_CLR_ON_MATCH_EN BIT(1) |
| #define TIMER_ENABLE_EN BIT(0) |
| #define TIMER_CLEAR 0x000C |
| #define DGT_CLK_CTL 0x10 |
| #define DGT_CLK_CTL_DIV_4 0x3 |
| #define TIMER_STS_GPT0_CLR_PEND BIT(10) |
| |
| #define GPT_HZ 32768 |
| |
| #define MSM_DGT_SHIFT 5 |
| |
| static void __iomem *event_base; |
| static void __iomem *sts_base; |
| |
| static irqreturn_t msm_timer_interrupt(int irq, void *dev_id) |
| { |
| struct clock_event_device *evt = dev_id; |
| /* Stop the timer tick */ |
| if (evt->mode == CLOCK_EVT_MODE_ONESHOT) { |
| u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE); |
| ctrl &= ~TIMER_ENABLE_EN; |
| writel_relaxed(ctrl, event_base + TIMER_ENABLE); |
| } |
| evt->event_handler(evt); |
| return IRQ_HANDLED; |
| } |
| |
| static int msm_timer_set_next_event(unsigned long cycles, |
| struct clock_event_device *evt) |
| { |
| u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE); |
| |
| ctrl &= ~TIMER_ENABLE_EN; |
| writel_relaxed(ctrl, event_base + TIMER_ENABLE); |
| |
| writel_relaxed(ctrl, event_base + TIMER_CLEAR); |
| writel_relaxed(cycles, event_base + TIMER_MATCH_VAL); |
| |
| if (sts_base) |
| while (readl_relaxed(sts_base) & TIMER_STS_GPT0_CLR_PEND) |
| cpu_relax(); |
| |
| writel_relaxed(ctrl | TIMER_ENABLE_EN, event_base + TIMER_ENABLE); |
| return 0; |
| } |
| |
| static void msm_timer_set_mode(enum clock_event_mode mode, |
| struct clock_event_device *evt) |
| { |
| u32 ctrl; |
| |
| ctrl = readl_relaxed(event_base + TIMER_ENABLE); |
| ctrl &= ~(TIMER_ENABLE_EN | TIMER_ENABLE_CLR_ON_MATCH_EN); |
| |
| switch (mode) { |
| case CLOCK_EVT_MODE_RESUME: |
| case CLOCK_EVT_MODE_PERIODIC: |
| break; |
| case CLOCK_EVT_MODE_ONESHOT: |
| /* Timer is enabled in set_next_event */ |
| break; |
| case CLOCK_EVT_MODE_UNUSED: |
| case CLOCK_EVT_MODE_SHUTDOWN: |
| break; |
| } |
| writel_relaxed(ctrl, event_base + TIMER_ENABLE); |
| } |
| |
| static struct clock_event_device __percpu *msm_evt; |
| |
| static void __iomem *source_base; |
| |
| static notrace cycle_t msm_read_timer_count(struct clocksource *cs) |
| { |
| return readl_relaxed(source_base + TIMER_COUNT_VAL); |
| } |
| |
| static notrace cycle_t msm_read_timer_count_shift(struct clocksource *cs) |
| { |
| /* |
| * Shift timer count down by a constant due to unreliable lower bits |
| * on some targets. |
| */ |
| return msm_read_timer_count(cs) >> MSM_DGT_SHIFT; |
| } |
| |
| static struct clocksource msm_clocksource = { |
| .name = "dg_timer", |
| .rating = 300, |
| .read = msm_read_timer_count, |
| .mask = CLOCKSOURCE_MASK(32), |
| .flags = CLOCK_SOURCE_IS_CONTINUOUS, |
| }; |
| |
| static int msm_timer_irq; |
| static int msm_timer_has_ppi; |
| |
| static int msm_local_timer_setup(struct clock_event_device *evt) |
| { |
| int cpu = smp_processor_id(); |
| int err; |
| |
| evt->irq = msm_timer_irq; |
| evt->name = "msm_timer"; |
| evt->features = CLOCK_EVT_FEAT_ONESHOT; |
| evt->rating = 200; |
| evt->set_mode = msm_timer_set_mode; |
| evt->set_next_event = msm_timer_set_next_event; |
| evt->cpumask = cpumask_of(cpu); |
| |
| clockevents_config_and_register(evt, GPT_HZ, 4, 0xffffffff); |
| |
| if (msm_timer_has_ppi) { |
| enable_percpu_irq(evt->irq, IRQ_TYPE_EDGE_RISING); |
| } else { |
| err = request_irq(evt->irq, msm_timer_interrupt, |
| IRQF_TIMER | IRQF_NOBALANCING | |
| IRQF_TRIGGER_RISING, "gp_timer", evt); |
| if (err) |
| pr_err("request_irq failed\n"); |
| } |
| |
| return 0; |
| } |
| |
| static void msm_local_timer_stop(struct clock_event_device *evt) |
| { |
| evt->set_mode(CLOCK_EVT_MODE_UNUSED, evt); |
| disable_percpu_irq(evt->irq); |
| } |
| |
| static int msm_timer_cpu_notify(struct notifier_block *self, |
| unsigned long action, void *hcpu) |
| { |
| /* |
| * Grab cpu pointer in each case to avoid spurious |
| * preemptible warnings |
| */ |
| switch (action & ~CPU_TASKS_FROZEN) { |
| case CPU_STARTING: |
| msm_local_timer_setup(this_cpu_ptr(msm_evt)); |
| break; |
| case CPU_DYING: |
| msm_local_timer_stop(this_cpu_ptr(msm_evt)); |
| break; |
| } |
| |
| return NOTIFY_OK; |
| } |
| |
| static struct notifier_block msm_timer_cpu_nb = { |
| .notifier_call = msm_timer_cpu_notify, |
| }; |
| |
| static notrace u32 msm_sched_clock_read(void) |
| { |
| return msm_clocksource.read(&msm_clocksource); |
| } |
| |
| static void __init msm_timer_init(u32 dgt_hz, int sched_bits, int irq, |
| bool percpu) |
| { |
| struct clocksource *cs = &msm_clocksource; |
| int res = 0; |
| |
| msm_timer_irq = irq; |
| msm_timer_has_ppi = percpu; |
| |
| msm_evt = alloc_percpu(struct clock_event_device); |
| if (!msm_evt) { |
| pr_err("memory allocation failed for clockevents\n"); |
| goto err; |
| } |
| |
| if (percpu) |
| res = request_percpu_irq(irq, msm_timer_interrupt, |
| "gp_timer", msm_evt); |
| |
| if (res) { |
| pr_err("request_percpu_irq failed\n"); |
| } else { |
| res = register_cpu_notifier(&msm_timer_cpu_nb); |
| if (res) { |
| free_percpu_irq(irq, msm_evt); |
| goto err; |
| } |
| |
| /* Immediately configure the timer on the boot CPU */ |
| msm_local_timer_setup(__this_cpu_ptr(msm_evt)); |
| } |
| |
| err: |
| writel_relaxed(TIMER_ENABLE_EN, source_base + TIMER_ENABLE); |
| res = clocksource_register_hz(cs, dgt_hz); |
| if (res) |
| pr_err("clocksource_register failed\n"); |
| setup_sched_clock(msm_sched_clock_read, sched_bits, dgt_hz); |
| } |
| |
| #ifdef CONFIG_OF |
| static void __init msm_dt_timer_init(struct device_node *np) |
| { |
| u32 freq; |
| int irq; |
| struct resource res; |
| u32 percpu_offset; |
| void __iomem *base; |
| void __iomem *cpu0_base; |
| |
| base = of_iomap(np, 0); |
| if (!base) { |
| pr_err("Failed to map event base\n"); |
| return; |
| } |
| |
| /* We use GPT0 for the clockevent */ |
| irq = irq_of_parse_and_map(np, 1); |
| if (irq <= 0) { |
| pr_err("Can't get irq\n"); |
| return; |
| } |
| |
| /* We use CPU0's DGT for the clocksource */ |
| if (of_property_read_u32(np, "cpu-offset", &percpu_offset)) |
| percpu_offset = 0; |
| |
| if (of_address_to_resource(np, 0, &res)) { |
| pr_err("Failed to parse DGT resource\n"); |
| return; |
| } |
| |
| cpu0_base = ioremap(res.start + percpu_offset, resource_size(&res)); |
| if (!cpu0_base) { |
| pr_err("Failed to map source base\n"); |
| return; |
| } |
| |
| if (of_property_read_u32(np, "clock-frequency", &freq)) { |
| pr_err("Unknown frequency\n"); |
| return; |
| } |
| |
| event_base = base + 0x4; |
| sts_base = base + 0x88; |
| source_base = cpu0_base + 0x24; |
| freq /= 4; |
| writel_relaxed(DGT_CLK_CTL_DIV_4, source_base + DGT_CLK_CTL); |
| |
| msm_timer_init(freq, 32, irq, !!percpu_offset); |
| } |
| CLOCKSOURCE_OF_DECLARE(kpss_timer, "qcom,kpss-timer", msm_dt_timer_init); |
| CLOCKSOURCE_OF_DECLARE(scss_timer, "qcom,scss-timer", msm_dt_timer_init); |
| #endif |
| |
| static int __init msm_timer_map(phys_addr_t addr, u32 event, u32 source, |
| u32 sts) |
| { |
| void __iomem *base; |
| |
| base = ioremap(addr, SZ_256); |
| if (!base) { |
| pr_err("Failed to map timer base\n"); |
| return -ENOMEM; |
| } |
| event_base = base + event; |
| source_base = base + source; |
| if (sts) |
| sts_base = base + sts; |
| |
| return 0; |
| } |
| |
| void __init msm7x01_timer_init(void) |
| { |
| struct clocksource *cs = &msm_clocksource; |
| |
| if (msm_timer_map(0xc0100000, 0x0, 0x10, 0x0)) |
| return; |
| cs->read = msm_read_timer_count_shift; |
| cs->mask = CLOCKSOURCE_MASK((32 - MSM_DGT_SHIFT)); |
| /* 600 KHz */ |
| msm_timer_init(19200000 >> MSM_DGT_SHIFT, 32 - MSM_DGT_SHIFT, 7, |
| false); |
| } |
| |
| void __init msm7x30_timer_init(void) |
| { |
| if (msm_timer_map(0xc0100000, 0x4, 0x24, 0x80)) |
| return; |
| msm_timer_init(24576000 / 4, 32, 1, false); |
| } |
| |
| void __init qsd8x50_timer_init(void) |
| { |
| if (msm_timer_map(0xAC100000, 0x0, 0x10, 0x34)) |
| return; |
| msm_timer_init(19200000 / 4, 32, 7, false); |
| } |